Fastener having clamping head



April 22, 1952 o. J. PouPlTH 2,594,211

F'ASTENER HAVING CLAMPING HEAD Filed July 27, 1948 2 SHEETS- SHEET .1`

April 22, l952 o. J. PoLJPrrcl-ll 2,594,211

FASTENER HAVING CLAMPING HEAD Filed July 27, 1948 SHEETS-SHEET 2 INVENTOR.

Patented Apr. 22, 1952 FAs'rENER HAVING CLAMP-ING HEAD Ouglje'sa Julesllroipitch, Chicago, Ill., assignor to Illinois Tool Works; Chcaio,l1l., a corporation Llof illinois applicetionJuly'av, 194s, 'serial No. 40,878

This invention relates generally to fastening devices `and more particularly to' fasteners of vthe type adapted for insertion within a Work Aaperture followed -byhammer blows applied to aprotruding portion of the fastener, thelatter serving to spread the inner extremity ofthe fastener.

It is an object of the present. invention to provide a fastener of the type referred to abovewhich will serve .to hold or secure work parts, as Lfor Aexample tubing or other devicesto which the unit may be adapted, in position upon a`work sheet or panel.

One of the potential hazards incident to the use of hammer driven fasteners is 1that of applying excessive or crushing pressures to the part to be secured, .and the present invention oontemplates a fastener which, although adap'ted"to be `hammer driven, will .res`ili`ently,Y .yet lrxnly clamp a work part in place without the slightest danger of `applying excessive pressures. To lthis end, a fastener is contemplatedhaving"accurately located abutment means for vlimiting `the extent of movement of the work clamping portion of the fastener. A fastener is'thus'providedtparticularly adapted .for holding "frafngibl'e` Work pieces, but also equallyusable"fonholding various types and kinds of Work pieces to Lwhichitlmay be shaped and adapted;

More specifically, it isan'object of thepresent invention to provide an improved andi'elatlvely inexpensive fastener of "the nature previouslylreferred to, which may be formed "from a single length of resilient stock and which is "of Iblind fastener form capable of being 'inserted andfsecured in position from oneside ofithe'work aperture.

Another object of the present inventionis4 to provide a blind `fastener which lnot'vnly serves to clamp 'the part against a `worksurface as'mentioned above but also assures vspreading of "the fastener shank at Athe opposite "end `so 4as 4to enlable the fastener to be-used 'withequal-fac'ility for various thicknesses of "workpieces The present invention alsol contemplates-a lhammer driven rivet-type `fastenerformedfrom a v-`Claims. (01:5248-468) 1" is a. perspective view of a fastener 'which -is representative of one embodiment ofthe present invention;

Fig. 2 discloses the fastener of Fig. lfapplied to a lwork piece for the purpose of clampingly securing two tubular work parts in place;

Fig. 3 is a view taken substantially along Vthe line 3 3 ofFig. 2;

Fig. `4 is a perspective view similar `to Fig. 1 illustrating a slightly modified form of fastener provided with abutments or shoulders f'orlimit- `ing the extent to which the fastener'protuberance may be hammer driven into position;

Fig. 5 is a view'similar to Fig. 2 illustrating a slightly modified fastener in which only oneex- "tremity thereof i's providedwith means for accommodating or `clampingly engaging a work part;

' Fig. 6 is a View similar to Figs. 2 and 5 illustrating a further modified form of the fastener which `is provided with resilient head portions adapted to cooperate with the oppositely disposed spread shank portions to secure two work sheets together, and if desired to also hold a work-part in place;

Fig. 7 illustrates the sheet metal blank from whichthe fastener of Figs. 1 ltoV 3 inclusive'may befomed;

Fig. 8 is aplan view of the blank` used for )producing thefastener of Fig. 4;

AFigi 9 is 1a plan view of the blank similar to Fig. 7, differing from Fig. 7 in that the shank vportion ofthe 'fastener is provided with a taper so as Vto enable the fastener to wedge itselfwithin a work aperture and' thus limit vthe extent to which thes'hank may be driven into said aperture;

Fig. is'aperspective View of a modified form A of fastener, adapted for holding a molding strip or ,the"like;

. Fig. 11 is an elevational view of the structure .of Fig.' 10, in holding position, andapplied to `A"'FigL 1'2s a perspectiveview of a further modiined "embodiment, "the'fastener embodyingreinforcingand other features presently to Abe described;

` Fig. 13 is an elevational View of thefastener of Fig. 12, in holding position;

""lig. 14 is'avertical sectional view of the'fastener 'ofFig 12 on the line |4--I4 thereof;

v15. isv a vhorizontal sectional view ofthe structureof'Fig. 13, along the line |5-l 'thereof; and

"Fig 16 is a detail view, on la -reducedscale,

3 of the blank, partly formed, used in fabricating the fastener of Figs. 12-15.

Referring now to the drawings more in detail wherein like numerals have been employed to designate similar parts throughout the various figures, it will be seen that one embodimentl of the present invention is illustrated in Figs. 1 to 3 inclusive, the fastener in said figures being designated generally 4by the numeral i0. This fastener I is preferably formed from a single elongated strip of sheet metal stock having the form illustrated by the blank of Fig. '7. In producing the fastener IQ from this blank it is Abent intermediate its ends vto provide adjacent shank portions I2 and i4. Before application to a work piece these shank portions |2-l4 appear as illustrated in Fig. 1 witlifa portion thereof projecting upwardly in theform of a protuberance I8. The blank is then bentback upon itself to provide shank portions lf'and 20. The upper extremities of these shank portions, I8 and 20 support arcuate clamping'l members or heads 22 and 24 respectively. Y

The fastener is applied to a work sheet as for example the work piece 26 of Fig. 2 by inserting the shank portions I2l4-8-29 (all of which parts are designated generally by the numeral 28) within a work aperture 30. The aperture 30 maybe just large enough to loosely accommodate the shank 28 or fit may be slightly smaller than the maximum cross-section o the shank 28, thus requiring the shank to be slightly compressed to permit of insertion. The latter arrangement enables initial snug fitting of the fastener shank within "the aperture prior to the application of hammer blows against the protuberance I6.

In Fig. 2 the arcuate work clamping members or heads 22-24 embrace the complementary curved periphery of work parts or tubes 32. As the fastener In is initially inserted within the work aperture 30 the "resilient work clamping members 22-211are moved into engagement with the complementary surfaces of tubes 32. Hammer blows are then applied to the outer extremity ofthe protuberance Hir which causes abutments or shoulders 34--36 associated with the clamping members 22-24 respectively to be moved into engagement with the outer surfaces of the work piece 26 and the innerfshank portion 28 spreads laterally as illustrated-in Fig. 2. The shoulders or abutments 34--36 limit the extent to which the resilient clamping'members 22--24 may be shifted in response to hammer blows upon the protuberance IB. When these shoulders are in engagement with the work surface the work parts or tubes 32 will be resiliently yet rmly held in place and the pressure exerted by the arcuate clamping members 22-24 is not in excess of the strength of the material from which the tubes 32 are formed. That is to say, the fastener is of such a nature that work parts may be firmly and resiliently held in place without any impairment which might otherwise result from the application of excessive clamping pressures. The spreading of the shank 28 draws the abutments 34-36 tightly against thework surface thereby providing a very secure fastener.

It will also be understood from the foregoing description` that the fastener illustrated in Figs. 1 to 3 inclusive may be used with work pieces of various thicknesses. In other words, the fastener is not limited for use with workpieces ofy any' given thickness. With view of adding strength and rigidity to the arcuate work clamphammer blows.

ing members they are provided with a central rib 38. While these ribs 38 lend a certain amount of rigidity it should be understood that the clamping members 22-24 are sufficiently resilient to afford desired yieldable contact or clamping engagement with the work parts 32.

In Fig. 4 a slightly modified fastener designated generally by the numeral Ill-a is illustrated. The only structural difference between the fastener iii-a and the fastener IE resides in the provision of shoulders or abutments 40 which limit the extent to which the protuberance I6 may be driven axially in response to the application of While the fastener ID incorporates shoulders 34-36 to limit the extent to which the clamping members may be urged toward the work, abutments 4t of the fastener |0-a limit the extent of the deformation or spreading of the shank 28. In Fig, 4 the various parts of the fastener corresponding with parts identical to the fastener lil are similarly numbered, but bear the suffix a. The blank from which the fastener Ill-a may be produced is illustrated in Fig. 8.

InFig. 5 a slightly modified fastener is shown which is designated generally by the numeral lll-b. This fastener incorporates a single work clamping member 2li-b. rIhis Work clamping member 2li-b is open-sided to permit the insertion or withdrawal of a Work part after the fastener..has -been secured in place. In all other respects the fastener ID-b is similar Vto the fastener Ill eX-cept that the protrudngportion or projection lli-b and the associated shank portions lZ-b-lll-b, and I8-b--2ll-b` are formed from a blank having the taper illustrated in Fig. 9.' the protuberance lli-b can only be driven into Y the work to the point where the side edges thereof lwedge themselves into the work aperture 30. Of course the structure of Fig. 5 maybe made from a blankl similar to the blanks shown in Fig. '7 and Fig. 8. Y

In Fig. 6 a further modification of the fastener is shown designated generally by the numeral Ill-c. This fastener is similar to the fastener IO-a illustrated in Fig. 4, with the exception that the 'work engaging members 22-c-24-c are substantially circular in cross-section. This arrangement `providesla resilient head structure which when used in association with a. pair of work pieces or sheetsV l2- 44, cooperates with the expanded shank 28-c in clamping said work sheets together. The circular members'ZZ-c- 24-c, inaddition to providing resilient head portions, may also be employed as holding means for work parts. Y Y

i In instances where it is desirable to retain the fastener within the work aperture before hammer blows are applied to the protuberance, the arms of shank 28-b as illustrated inFig. 5 may be flared outwardly to a slight degree. This requires the shank arms to be compressed toward each other in order to pass them through the work aperture, and as they springV outwardly again they provide sufficient frictional contact with the work material dening the aperture 30 to prevent the fastener from becoming inadvertently dislodged from the aperture. That is to say, by outwardly flaring the shank arms a temporary retention means isprovided. It might be said that the shank portion of each of the fasteners illustrated in the accompanying drawings comiprises strips of elongated resilient sheet stock, portions of which are bent back upon themselves to providev outer arms and inner adjacent arms,

By having this tapered configuration wherein the portions of the inner and outer arms areyinsertablethrougha work aperture normally diverging from each other in the vicinity of their entering extremities to facilitate initial assembly of said fastener with an apertured work piece.

:LA blind vfastener comprising an elongated strip V, of sheet material having different widths along its length and bent into substantially Wfshape to provide outer arms and adjacently positioned inner arms extending in general parallelism, the bends connecting the outer arms to the inner arms forming the entering end of the fastener, said outer arms and adjacent portions of the `inner arms having a length greater than the thickness of the apertured work through which said arms are to be inserted, axial continuatiqns of said outer arms being abruptly widened along their longitudinal margins to provide Work engaging shoulders, a head section extending axiallyfand diverging radially outwardlyjfrom Vat least' one of said shoulders to present an object clamping surface having a portion thereof spaced axially from a plane coincident with said shoulders, said inner arms extendingY axially beyond saidshoulders in position to be engaged by a suitable pressure applying tool after the entering end of the fastener has been inserted into a work aperture, said shoulders serving to limit theextent of axial movement of said outer arms in the direction of the applied force so as accurately to position the object clamping surface with respect to the surface of a complemental work piece, said outer arms being adapted, as an incident to the axial shifting thereof, to spread laterally and, thereby coact with said shoulders in gripping a work piece therebetween, and work engaging abutments on said inner arms to limit the V extent to which the said inner arms may be axially shifted with respect to the work piece.

5. A blind fastener as set forth in' claim 4, wherein the head section consists of axially and radiallyY diverging continuations of ,the outer arms so as to provide a pair of object clamping surfaces. Y

' OUGLJESA JULES POUPITCH.

REFERENCES CITED The following references are of record in the le of this patent:

-`UNITED STATES PATENTS 

